#app1{
  height: 50vh;
  width: 50vw;
}
#app1 .output{
  font-size: 26px;
  padding: 10px;
}
#app1 .actions{
  padding: 20px;
}
#app1 button  {
  padding: 4px 8px;
  margin-right: 5px;
}